The invention relates generally to systems and methods for monitoring health of rotor blades.
Rotor blades or rotating blades are used in many devices with several examples including compressors, turbines, and engines. An axial compressor, for example, has a series of stages with each stage comprising a row of rotor blades followed by a row of stator blades.
Axial compressors are used in a number of devices with one example being land based gas turbines. Land based gas turbines typically include an inlet section to accelerate the air, a compressor to compress the incoming air, a combustor for burning compressed air and fuel, and a turbine to covert thermal energy into mechanical energy to drive a generator to produce required power. To develop adequate pressure for combustion, the compressor has about eighteen stages with each stage having stator and rotor blades. Each blade of the compressor has distinct natural frequencies.
Various factors adversely affect health of the rotor blades and lead to fatigue, stress, and ultimately cracking of the rotor blades. When a rotor blade crack propagates and reaches a critical limit, the rotor blade is broken away from the rotor.
Thus, it is beneficial to predict health of the rotor blades in real time. By predicting cracks in real time, for example, failures of the devices in which the blades operate can be reduced.